Some of the data used to generate this chart is derived from Baseball Musings' Day-by-day database.

Rk.: The author's ranking of that pitcher for that day only. T: Pitcher throws left-handed or right-handed. Opp: The pitcher's opponent for the day. QR: "Quality Rating," or the starting pitcher's matchup rating -- separate from the author's ranking -- which accounts for past history (three years' worth as well as past 21 days), opponent and ballpark. OPS is the primary statistic used in the calculation. Ratings range from 1-10, with 10 representing the best possible matchup, statistically speaking, and 1 representing the worst. So, for example, a 10 is a must-start rating, while a 1 should be avoided (if possible); a 1-2 is poor, 3-4 is fair, 5-6 is average, 7-8 is very good and 9-10 is excellent. W-L: Pitcher's win-loss record. ERA: Pitcher's earned run average. WHIP: Pitcher's average number of walks plus hits surrendered per inning.

Thursday's MLB schedule features the fewest aces I have seen all season, as there are just three pitchers owned in at least 60 percent of the ESPN.com universe (Zack Greinke, Jake Peavy and Matt Cain). There are two others who used to be owned in the vast majority of leagues (Jeff Locke and Jeremy Hellickson), but both are pitching too poorly right now to be considered start-worthy for any fantasy format. A.J. Griffin (57 percent ownership) is the only other Thursday pitcher sitting on more ESPN.com rosters than waiver wires, but I still think the following four names are worthy of a pickup in most mixed leagues, and especially in NL-only formats:

Tyson Ross (18 percent ESPN.com fantasy ownership) continues to dazzle since his re-insertion into the San Diego Padres' rotation on July 23. In these nine starts, the right-hander is 3-3 with a 2.16 ERA, 0.94 WHIP, .189 opponent BA and 9.7 K/9. These impressive numbers aren't just a product of Petco Park, as five of these starts have come on the road, where he's gone 3-1 with a 1.97 ERA, 0.97 WHIP, .194 opponent BA and 9.8 K/9. These five away outings occurred at Dodger Stadium, Chase Field (twice), Great American Ball Park and Miller Park, yet none of these host lineups were able to take Ross over the fence, posting a powerless .250 slugging percentage combined. His Thursday opponent, the Philadelphia Phillies, haven't really been crushing the ball lately either, scoring 3.2 runs per game with a .228 BA and .352 SLG in their past 14 contests. Ross is worthy of a start in all fantasy formats for this matchup.

Roy Halladay (31 percent ESPN.com fantasy ownership), Ross' mound opponent, hasn't thrown back-to-back quality starts since mid-April, but I expect this skid to end on Thursday when he hosts the lowly Padres. Halladay started off September on a high note one week ago, limiting the Washington Nationals to just one run and eight base runners in six innings while dialing up five strikeouts. The right-hander has faced San Diego five times since signing with the Phillies, going 3-2 with a 2.15 ERA, 1.14 WHIP and 10.5 K/9 while holding them to an awful .574 OPS (.277 OBP and .297 SLG). Nobody on the current Padres roster has ever homered off Halladay in 119 collective plate appearances, compiling 27 K's and just six walks. And in case you're not following the bottom of the standings, San Diego has been atrocious in its past 14 road tilts, producing a 5-9 record with 3.3 runs and 8.1 strikeouts per game. Halladay is a viable starter in the vast majority of fantasy leagues on Thursday.

Tanner Roark (8 percent ESPN.com fantasy ownership) made a seamless transition from the bullpen to the rotation on Saturday, tossing six shutout innings against the Miami Marlins. The 26-year-old Roark allowed just four hits with zero walks and four strikeouts. He threw 71 pitches, so he'll probably be allowed to stretch into the 80s for his pitch count on Thursday when he visits the New York Mets. Roark has been an absolute beast on the road this season, going 3-0 with a 1.10 ERA, 0.74 WHIP, .189 opponent BA and 8.3 K/9. Expect more dominance against a Mets lineup that is back to its run-stranding ways, scoring just 2.9 runs per game in the past nine contests (2-7 record) despite a decent .306 on-base percentage. New York has fanned 8.6 times per game during this stretch of futility, while tallying just five homers. Roark should also bank on plenty of run support with his red-hot Washington Nationals (6-1 record, 6.0 runs per game, .873 OPS in past seven games) facing scrap-heap pickup Aaron Harang, who will be making his Mets debut. Before getting cut by the Seattle Mariners, Harang had an atrocious August, going 0-2 with a 9.12 ERA and 1.74 WHIP in five starts. This golden win opportunity for Roark makes him valuable to most fantasy owners on Thursday.

Joe Kelly (42 percent ESPN.com fantasy ownership) still hasn't lost in 11 straight starts since rejoining the St. Louis Cardinals' rotation on July 6, going 8-0 (his team is 10-1) with a 2.10 ERA despite a subpar 1.38 WHIP and 5.3 K/9. On Thursday, the right-hander hosts a Milwaukee Brewers club that has hit Kelly hard over the years (.329/.385/.427). However, they have not hit well over the past 10 games, where they have scored three runs or less in six of those contests and produced a 3-7 record. The Brew Crew is also 2-5 at Busch Stadium this season with just 20 runs (2.9 per game), 9.0 K's per game and a slash of .233/.281/.333. Kelly has thrown three straight quality starts at home (3-0, 2.00 ERA), and is certainly capable of doing it again on Thursday, making him worth a look in ultra-deep formats.

Hitter matchup ratings for September 12

Hitter Ratings

Hitter Ratings

Team

Overall

LHB

RHB

Steals

Team

Overall

LHB

RHB

Steals

No game scheduled

5

7

2

3

6

9

3

3

4

3

4

3

9

6

10

3

1

1

1

6

5

5

3

6

7

3

8

1

5

9

3

3

8

10

6

5

7

8

4

4

5

8

1

7

No game scheduled

9

1

10

6

8

7

8

4

4

1

9

6

No game scheduled

3

5

1

5

No game scheduled

3

5

1

1

No game scheduled

No game scheduled

No game scheduled

3

4

1

9

9

7

8

5

No game scheduled

2

1

1

6

6

8

2

7

8

10

5

7

7

7

6

4

Some of the data used to generate this chart is derived from Baseball Musings' Day-by-day database.

Hitter ratings account for the opposing starting pitcher's past history (three years' worth as well as past 21 days) as well as ballpark factors. "LHB" and "RHB" ratings account only for left- and right-handed batters, respectively. OPS is the primary statistic used in the calculation. Ratings range from 1-10, with 10 representing the best possible matchup, statistically speaking, and 1 representing the worst. So, for example, a 10 is a must-start rating, while a 1 should be avoided (if possible); a 1-2 is poor, 3-4 is fair, 5-6 is average, 7-8 is very good and 9-10 is excellent.

You might want to pick up Josmil Pinto, who has a well-hit average of .385 in September entering Wednesday, the second-highest rate among all MLB batters so far this month.

Batters have swung and missed on 31 percent of Tyson Ross' pitches since he rejoined the rotation in late July. That's the highest miss percentage against any pitcher during that span.

Since joining the Cardinals' rotation on July 6, Joe Kelly has been dominant. He's a perfect 8-0 and has allowed just 15 runs in 11 starts, which is tied for the second-fewest runs during that span entering Wednesday.

Tony Cingrani, SP, Cincinnati Reds: He exited Tuesday's start with back spasms and could miss the next couple of weeks as this is the same ailment that landed him on the DL in late August. If he can't make his next start, the team could try Johnny Cueto, who has not pitched since June 28 because of a lat injury.

Bud Norris, SP, Baltimore Orioles: He will not pitch on Friday because of a sore elbow, but it's unclear if he'll be able to pitch again in five days.

Paul Maholm, SP, Atlanta Braves: He will not make his next start on Friday because of recurring pain in his left elbow, but an MRI came back negative so he could rejoin the rotation sometime next week. David Hale will make a spot start on Friday.

Jason Castro, C, Houston Astros: He has not played since Saturday because of a recurring knee injury, and may soon be shut down for the season.

Dexter Fowler, OF, Colorado Rockies: He injured his left knee on Sept. 6 and hasn't played since. He's listed as day-to-day, and should return to action shortly.

Luis Jimenez, 3B, Los Angeles Angels: He exited the game on Sept. 7 after being hit on the right thumb with a pitch and hasn't played since. He's still considered day-to-day because of the contusion.

Khris Davis, OF, Milwaukee Brewers: He has not played since Sept. 4 because of a sore left wrist, and is considered day-to-day. An MRI came back negative, so expect him back on the field soon -- possibly Thursday.

On the mend:

David Wright, 3B, Mets: He ran the bases on Wednesday for the first time since straining his right hamstring, and hopes to return to the Mets next week.

Colby Rasmus, OF, Blue Jays: He expects to return to the lineup by the end of this week. Rasmus has been out since Aug. 11 with an oblique injury.

Other notes:

Jhonny Peralta, SS, Detroit Tigers: He's been allowed to resume workouts with the Tigers despite not being eligible to return from his 50-game PED suspension. The team has not decided whether it will activate Peralta.

Derek Jeter, SS, New York Yankees: He has been shut down for the remainder of the 2013 season because of recurring pain in his surgically repaired ankle. Brendan Ryan, who was acquired from the Seattle Mariners on Tuesday for a player to be named, will likely be the Yankees' starting shortstop for the remainder of the regular season, but is not eligible for New York's playoff roster if the Yankees reach the postseason.

Alex Wood, SP, Braves: He skipped his Thursday start to get extra rest after two straight poor outings. Veteran Freddy Garcia started in Wood's place on Thursday.